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Prévost J, Chen Y, Zhou F, Tolbert WD, Gasser R, Medjahed H, Nayrac M, Nguyen DN, Gottumukkala S, Hessell AJ, Rao VB, Pozharski E, Huang RK, Matthies D, Finzi A, Pazgier M. Structure-function analyses reveal key molecular determinants of HIV-1 CRF01_AE resistance to the entry inhibitor temsavir. Nat Commun 2023; 14:6710. [PMID: 37872202 PMCID: PMC10593844 DOI: 10.1038/s41467-023-42500-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 10/12/2023] [Indexed: 10/25/2023] Open
Abstract
The HIV-1 entry inhibitor temsavir prevents the viral receptor CD4 (cluster of differentiation 4) from interacting with the envelope glycoprotein (Env) and blocks its conformational changes. To do this, temsavir relies on the presence of a residue with small side chain at position 375 in Env and is unable to neutralize viral strains like CRF01_AE carrying His375. Here we investigate the mechanism of temsavir resistance and show that residue 375 is not the sole determinant of resistance. At least six additional residues within the gp120 inner domain layers, including five distant from the drug-binding pocket, contribute to resistance. A detailed structure-function analysis using engineered viruses and soluble trimer variants reveals that the molecular basis of resistance is mediated by crosstalk between His375 and the inner domain layers. Furthermore, our data confirm that temsavir can adjust its binding mode to accommodate changes in Env conformation, a property that likely contributes to its broad antiviral activity.
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Affiliation(s)
- Jérémie Prévost
- Centre de Recherche du CHUM, Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | - Yaozong Chen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Fei Zhou
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - William D Tolbert
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Romain Gasser
- Centre de Recherche du CHUM, Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | | | - Manon Nayrac
- Centre de Recherche du CHUM, Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | - Dung N Nguyen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Suneetha Gottumukkala
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Ann J Hessell
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, USA
| | - Venigalla B Rao
- Department of Biology, the Catholic University of America, Washington, DC, USA
| | - Edwin Pozharski
- Institute for Bioscience and Biotechnology Research, Rockville, MD, 20850, USA
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Rick K Huang
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, USA
| | - Doreen Matthies
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, QC, Canada.
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada.
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA.
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2
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Tolbert WD, Chen Y, Sun L, Benlarbi M, Ding S, Manickam R, Pangaro E, Nguyen DN, Gottumukkala S, Côté M, Gonzalez FJ, Finzi A, Tehrani ZR, Sajadi MM, Pazgier M. The molecular basis of the neutralization breadth of the RBD-specific antibody CoV11. Front Immunol 2023; 14:1178355. [PMID: 37334379 PMCID: PMC10272436 DOI: 10.3389/fimmu.2023.1178355] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 05/16/2023] [Indexed: 06/20/2023] Open
Abstract
SARS-CoV-2, the virus behind the COVID-19 pandemic, has changed over time to the extent that the current virus is substantially different from what originally led to the pandemic in 2019-2020. Viral variants have modified the severity and transmissibility of the disease and continue do so. How much of this change is due to viral fitness versus a response to immune pressure is hard to define. One class of antibodies that continues to afford some level of protection from emerging variants are those that closely overlap the binding site for angiotensin-converting enzyme 2 (ACE2) on the receptor binding domain (RBD). Some members of this class that were identified early in the course of the pandemic arose from the VH 3-53 germline gene (IGHV3-53*01) and had short heavy chain complementarity-determining region 3s (CDR H3s). Here, we describe the molecular basis of the SARS-CoV-2 RBD recognition by the anti-RBD monoclonal antibody CoV11 isolated early in the COVID-19 pandemic and show how its unique mode of binding the RBD determines its neutralization breadth. CoV11 utilizes a heavy chain VH 3-53 and a light chain VK 3-20 germline sequence to bind to the RBD. Two of CoV11's four heavy chain changes from the VH 3-53 germline sequence, T h r F W R H 1 28 to Ile and S e r C D R H 1 31 to Arg, and some unique features in its CDR H3 increase its affinity to the RBD, while the four light chain changes from the VK 3-20 germline sequence sit outside of the RBD binding site. Antibodies of this type can retain significant affinity and neutralization potency against variants of concern (VOCs) that have diverged significantly from original virus lineage such as the prevalent omicron variant. We also discuss the mechanism by which VH 3-53 encoded antibodies recognize spike antigen and show how minimal changes to their sequence, their choice of light chain, and their mode of binding influence their affinity and impact their neutralization breadth.
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Affiliation(s)
- William D. Tolbert
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Yaozong Chen
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Lulu Sun
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Mehdi Benlarbi
- Centre de recherche du Centre hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | - Shilei Ding
- Centre de recherche du Centre hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
| | - Rohini Manickam
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Emily Pangaro
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Dung N. Nguyen
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Suneetha Gottumukkala
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Marceline Côté
- Department of Biochemistry, Microbiology and Immunology, and Centre for Infection, Immunity, and Inflammation, University of Ottawa, Ottawa, ON, Canada
| | - Frank J. Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health (NIH), Bethesda, MD, United States
| | - Andrés Finzi
- Centre de recherche du Centre hospitalier de l'Université de Montréal (CHUM), Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | - Zahra R. Tehrani
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
- Division of Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Mohammad M. Sajadi
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
- Division of Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
- Department of Medicine, Baltimore Veterans Health Administration (VA) Medical Center, Baltimore, MD, United States
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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3
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Chen Y, Prévost J, Ullah I, Romero H, Lisi V, Tolbert WD, Grover JR, Ding S, Gong SY, Beaudoin-Bussières G, Gasser R, Benlarbi M, Vézina D, Anand SP, Chatterjee D, Goyette G, Grunst MW, Yang Z, Bo Y, Zhou F, Béland K, Bai X, Zeher AR, Huang RK, Nguyen DN, Sherburn R, Wu D, Piszczek G, Paré B, Matthies D, Xia D, Richard J, Kumar P, Mothes W, Côté M, Uchil PD, Lavallée VP, Smith MA, Pazgier M, Haddad E, Finzi A. Molecular basis for antiviral activity of two pediatric neutralizing antibodies targeting SARS-CoV-2 Spike RBD. iScience 2023; 26:105783. [PMID: 36514310 PMCID: PMC9733284 DOI: 10.1016/j.isci.2022.105783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 11/07/2022] [Accepted: 12/07/2022] [Indexed: 12/13/2022] Open
Abstract
Neutralizing antibodies (NAbs) hold great promise for clinical interventions against SARS-CoV-2 variants of concern (VOCs). Understanding NAb epitope-dependent antiviral mechanisms is crucial for developing vaccines and therapeutics against VOCs. Here we characterized two potent NAbs, EH3 and EH8, isolated from an unvaccinated pediatric patient with exceptional plasma neutralization activity. EH3 and EH8 cross-neutralize the early VOCs and mediate strong Fc-dependent effector activity in vitro. Structural analyses of EH3 and EH8 in complex with the receptor-binding domain (RBD) revealed the molecular determinants of the epitope-driven protection and VOC evasion. While EH3 represents the prevalent IGHV3-53 NAb whose epitope substantially overlaps with the ACE2 binding site, EH8 recognizes a narrow epitope exposed in both RBD-up and RBD-down conformations. When tested in vivo, a single-dose prophylactic administration of EH3 fully protected stringent K18-hACE2 mice from lethal challenge with Delta VOC. Our study demonstrates that protective NAbs responses converge in pediatric and adult SARS-CoV-2 patients.
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Affiliation(s)
- Yaozong Chen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Jérémie Prévost
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Irfan Ullah
- Department of Internal Medicine, Section of Infectious Diseases, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Hugo Romero
- Centre de Recherche du CHU Ste-Justine, Montreal, QC H3T 1C5, Canada
| | - Veronique Lisi
- Centre de Recherche du CHU Ste-Justine, Montreal, QC H3T 1C5, Canada
| | - William D. Tolbert
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Jonathan R. Grover
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Shilei Ding
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
| | - Shang Yu Gong
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, QC H3A 2B4, Canada
| | - Guillaume Beaudoin-Bussières
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Romain Gasser
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Mehdi Benlarbi
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
| | - Dani Vézina
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
| | - Sai Priya Anand
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, QC H3A 2B4, Canada
| | | | | | - Michael W. Grunst
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Ziwei Yang
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Yuxia Bo
- Department of Biochemistry, Microbiology and Immunology, Center for Infection, Immunity, and Inflammation, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Fei Zhou
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kathie Béland
- Centre de Recherche du CHU Ste-Justine, Montreal, QC H3T 1C5, Canada
| | - Xiaoyun Bai
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Allison R. Zeher
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rick K. Huang
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dung N. Nguyen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Rebekah Sherburn
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Di Wu
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Grzegorz Piszczek
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Bastien Paré
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Doreen Matthies
- Unit on Structural Biology, Division of Basic and Translational Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Di Xia
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jonathan Richard
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Priti Kumar
- Department of Internal Medicine, Section of Infectious Diseases, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Walther Mothes
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Marceline Côté
- Department of Biochemistry, Microbiology and Immunology, Center for Infection, Immunity, and Inflammation, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Pradeep D. Uchil
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Vincent-Philippe Lavallée
- Centre de Recherche du CHU Ste-Justine, Montreal, QC H3T 1C5, Canada
- Division of Pediatric Hematology-Oncology, Centre Hospitalier Universitaire (CHU) Sainte-Justine, Montréal, QC, Canada
- Département de Pédiatrie, Université de Montréal, Montreal, QC H3T 1C5, Canada
| | - Martin A. Smith
- Centre de Recherche du CHU Ste-Justine, Montreal, QC H3T 1C5, Canada
- Département de Biochimie et Médecine Moléculaire, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Elie Haddad
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
- Département de Pédiatrie, Université de Montréal, Montreal, QC H3T 1C5, Canada
| | - Andrés Finzi
- Centre de Recherche du CHUM (CRCHUM), Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, QC H3A 2B4, Canada
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Tolbert WD, Gohain N, Kremer PG, Hederman AP, Nguyen DN, Van V, Sherburn R, Lewis GK, Finzi A, Pollara J, Ackerman ME, Barb AW, Pazgier M. Decoding human-macaque interspecies differences in Fc-effector functions: The structural basis for CD16-dependent effector function in Rhesus macaques. Front Immunol 2022; 13:960411. [PMID: 36131913 PMCID: PMC9484259 DOI: 10.3389/fimmu.2022.960411] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 07/26/2022] [Indexed: 01/27/2023] Open
Abstract
Fc mediated effector functions of antibodies play important roles in immunotherapies and vaccine efficacy but assessing those functions in animal models can be challenging due to species differences. Rhesus macaques, Macaca mulatta (Mm) share approximately 93% sequence identity with humans but display important differences in their adaptive immune system that complicates their use in validating therapeutics and vaccines that rely on Fc effector functions. In contrast to humans, macaques only have one low affinity FcγRIII receptor, CD16, which shares a polymorphism at position 158 with human FcγRIIIa with Ile158 and Val158 variants. Here we describe structure-function relationships of the Ile/Val158 polymorphism in Mm FcγRIII. Our data indicate that the affinity of the allelic variants of Mm FcγRIII for the macaque IgG subclasses vary greatly with changes in glycan composition both on the Fc and the receptor. However, unlike the human Phe/Val158 polymorphism in FcγRIIIa, the higher affinity variant corresponds to the larger, more hydrophobic side chain, Ile, even though it is not directly involved in the binding interface. Instead, this side chain appears to modulate glycan-glycan interactions at the Fc/FcγRIII interface. Furthermore, changes in glycan composition on the receptor have a greater effect for the Val158 variant such that with oligomannose type glycans and with glycans only on Asn45 and Asn162, Val158 becomes the variant with higher affinity to Fc. These results have implications not only for the better interpretation of nonhuman primate studies but also for studies performed with human effector cells carrying different FcγRIIIa alleles.
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Affiliation(s)
- William D. Tolbert
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Neelakshi Gohain
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Paul G. Kremer
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Andrew P. Hederman
- Thayer School of Engineering, Dartmouth College, Hanover, NH, United States
| | - Dung N. Nguyen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Verna Van
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Rebekah Sherburn
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - George K. Lewis
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Andrés Finzi
- Centre de recherche du CHUM, Montreal, QC, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC, Canada
| | - Justin Pollara
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States
- Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States
- Center for Human Systems Immunology, Duke University School of Medicine, Durham, NC, United States
| | | | - Adam W. Barb
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
- Department of Chemistry, University of Georgia, Athens, GA, United States
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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5
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Chen Y, Sun L, Ullah I, Beaudoin-Bussières G, Anand SP, Hederman AP, Tolbert WD, Sherburn R, Nguyen DN, Marchitto L, Ding S, Wu D, Luo Y, Gottumukkala S, Moran S, Kumar P, Piszczek G, Mothes W, Ackerman ME, Finzi A, Uchil PD, Gonzalez FJ, Pazgier M. Engineered ACE2-Fc counters murine lethal SARS-CoV-2 infection through direct neutralization and Fc-effector activities. Sci Adv 2022; 8:eabn4188. [PMID: 35857504 PMCID: PMC9278865 DOI: 10.1126/sciadv.abn4188] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 05/27/2022] [Indexed: 05/27/2023]
Abstract
Soluble angiotensin-converting enzyme 2 (ACE2) constitutes an attractive antiviral capable of targeting a wide range of coronaviruses using ACE2 as their receptor. Using structure-guided approaches, we developed a series of bivalent ACE2-Fcs harboring functionally and structurally validated mutations that enhance severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor binding domain recognition by up to ~12-fold and remove angiotensin enzymatic activity. The lead variant M81 potently cross-neutralized SARS-CoV-2 variants of concern (VOCs), including Omicron, at subnanomolar half-maximal inhibitory concentration and was capable of robust Fc-effector functions, including antibody-dependent cellular cytotoxicity, phagocytosis, and complement deposition. When tested in a stringent K18-hACE2 mouse model, Fc-enhanced ACE2-Fc delayed death by 3 to 5 days or effectively resolved lethal SARS-CoV-2 infection in both prophylactic and therapeutic settings via the combined effects of neutralization and Fc-effector functions. These data add to the demonstrated utility of soluble ACE2 as a valuable SARS-CoV-2 antiviral and indicate that Fc-effector functions may constitute an important component of ACE2-Fc therapeutic activity.
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Affiliation(s)
- Yaozong Chen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Lulu Sun
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Irfan Ullah
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Guillaume Beaudoin-Bussières
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Sai Priya Anand
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada
| | | | - William D. Tolbert
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Rebekah Sherburn
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Dung N. Nguyen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Lorie Marchitto
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Shilei Ding
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada
| | - Di Wu
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yuhong Luo
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Suneetha Gottumukkala
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Sean Moran
- Biomedical Instrumentation Center, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD 20814, USA
| | - Priti Kumar
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Grzegorz Piszczek
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Walther Mothes
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | | | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada
| | - Pradeep D. Uchil
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Frank J. Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
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6
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Tolbert WD, Nguyen DN, Tuyishime M, Crowley AR, Chen Y, Jha S, Goodman D, Bekker V, Mudrak SV, DeVico AL, Lewis GK, Theis JF, Pinter A, Moody MA, Easterhoff D, Wiehe K, Pollara J, Saunders KO, Tomaras GD, Ackerman M, Ferrari G, Pazgier M. Structure and Fc-Effector Function of Rhesusized Variants of Human Anti-HIV-1 IgG1s. Front Immunol 2022; 12:787603. [PMID: 35069563 PMCID: PMC8770954 DOI: 10.3389/fimmu.2021.787603] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/09/2021] [Indexed: 01/14/2023] Open
Abstract
Passive transfer of monoclonal antibodies (mAbs) of human origin into Non-Human Primates (NHPs), especially those which function predominantly by a Fc-effector mechanism, requires an a priori preparation step, in which the human mAb is reengineered to an equivalent NHP IgG subclass. This can be achieved by changing both the Fc and Fab sequence while simultaneously maintaining the epitope specificity of the parent antibody. This Ab reengineering process, referred to as rhesusization, can be challenging because the simple grafting of the complementarity determining regions (CDRs) into an NHP IgG subclass may impact the functionality of the mAb. Here we describe the successful rhesusization of a set of human mAbs targeting HIV-1 envelope (Env) epitopes involved in potent Fc-effector function against the virus. This set includes a mAb targeting a linear gp120 V1V2 epitope isolated from a RV144 vaccinee, a gp120 conformational epitope within the Cluster A region isolated from a RV305 vaccinated individual, and a linear gp41 epitope within the immunodominant Cys-loop region commonly targeted by most HIV-1 infected individuals. Structural analyses confirm that the rhesusized variants bind their respective Env antigens with almost identical specificity preserving epitope footprints and most antigen-Fab atomic contacts with constant regions folded as in control RM IgG1s. In addition, functional analyses confirm preservation of the Fc effector function of the rhesusized mAbs including the ability to mediate Antibody Dependent Cell-mediated Cytotoxicity (ADCC) and antibody dependent cellular phagocytosis by monocytes (ADCP) and neutrophils (ADNP) with potencies comparable to native macaque antibodies of similar specificity. While the antibodies chosen here are relevant for the examination of the correlates of protection in HIV-1 vaccine trials, the methods used are generally applicable to antibodies for other purposes.
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Affiliation(s)
- William D. Tolbert
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Dung N. Nguyen
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Marina Tuyishime
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Center for Human Systems Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Andrew R. Crowley
- Thayer School of Engineering, Dartmouth College, Hanover, NH, United States
| | - Yaozong Chen
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Shalini Jha
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States
| | - Derrick Goodman
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Center for Human Systems Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Valerie Bekker
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Center for Human Systems Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Sarah V. Mudrak
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Center for Human Systems Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Anthony L. DeVico
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - George K. Lewis
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - James F. Theis
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ, United States
| | - Abraham Pinter
- Public Health Research Institute, New Jersey Medical School, Rutgers University, Newark, NJ, United States
| | - M. Anthony Moody
- Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Department of Pediatrics, Duke University School of Medicine, Durham, NC, United States
| | - David Easterhoff
- Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States
| | - Kevin Wiehe
- Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Department of Medicine, Duke University School of Medicine, Durham, NC, United States
| | - Justin Pollara
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Center for Human Systems Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Kevin O. Saunders
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States
| | - Georgia D. Tomaras
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Center for Human Systems Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Margaret Ackerman
- Thayer School of Engineering, Dartmouth College, Hanover, NH, United States
| | - Guido Ferrari
- Department of Surgery, Duke University School of Medicine, Durham, NC, United States,Human Vaccine Institute, Duke University School of Medicine, Durham, NC, United States,Center for Human Systems Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, MD, United States,*Correspondence: Marzena Pazgier,
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Chen Y, Sun L, Ullah I, Beaudoin-Bussières G, Anand SP, Hederman AP, Tolbert WD, Sherburn R, Nguyen DN, Marchitto L, Ding S, Wu D, Luo Y, Gottumukkala S, Moran S, Kumar P, Piszczek G, Mothes W, Ackerman ME, Finzi A, Uchil PD, Gonzalez FJ, Pazgier M. Engineered ACE2-Fc counters murine lethal SARS-CoV-2 infection through direct neutralization and Fc-effector activities. bioRxiv 2021:2021.11.24.469776. [PMID: 34845451 PMCID: PMC8629194 DOI: 10.1101/2021.11.24.469776] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Soluble Angiotensin-Converting Enzyme 2 (ACE2) constitutes an attractive antiviral capable of targeting a wide range of coronaviruses utilizing ACE2 as their receptor. Here, using structure-guided approaches, we developed divalent ACE2 molecules by grafting the extracellular ACE2-domain onto a human IgG1 or IgG3 (ACE2-Fc). These ACE2-Fcs harbor structurally validated mutations that enhance spike (S) binding and remove angiotensin enzymatic activity. The lead variant bound tightly to S, mediated in vitro neutralization of SARS-CoV-2 variants of concern (VOCs) with sub-nanomolar IC 50 and was capable of robust Fc-effector functions, including antibody-dependent-cellular cytotoxicity, phagocytosis and complement deposition. When tested in a stringent K18-hACE2 mouse model, it delayed death or effectively resolved lethal SARS-CoV-2 infection in a prophylactic or therapeutic setting utilizing the combined effect of neutralization and Fc-effector functions. These data confirm the utility of ACE2-Fcs as valuable agents in preventing and eliminating SARS-CoV-2 infection and demonstrate that ACE2-Fc therapeutic activity require Fc-effector functions.
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Affiliation(s)
- Yaozong Chen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
- equal contribution
| | - Lulu Sun
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, USA
- equal contribution
| | - Irfan Ullah
- Department of Internal Medicine, Section of Infectious Diseases, Yale University School of Medicine, New Haven, CT 06520, USA
- equal contribution
| | - Guillaume Beaudoin-Bussières
- Centre de recherche du CHUM. Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Sai Priya Anand
- Centre de recherche du CHUM. Montreal, QC H2X 0A9, Canada
- Department of Microbiology and Immunology, McGill, QC, Canada
| | | | - William D. Tolbert
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Rebekah Sherburn
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Dung N. Nguyen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Lorie Marchitto
- Centre de recherche du CHUM. Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Shilei Ding
- Centre de recherche du CHUM. Montreal, QC H2X 0A9, Canada
| | - Di Wu
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, 20892
| | - Yuhong Luo
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - Suneetha Gottumukkala
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
| | - Sean Moran
- Biomedical Instrumentation Center, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA
| | - Priti Kumar
- Department of Internal Medicine, Section of Infectious Diseases, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Grzegorz Piszczek
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, 20892
| | - Walther Mothes
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | | | - Andrés Finzi
- Centre de recherche du CHUM. Montreal, QC H2X 0A9, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
- Department of Microbiology and Immunology, McGill, QC, Canada
| | - Pradeep D. Uchil
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Frank J. Gonzalez
- Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA
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8
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Anand SP, Prévost J, Descôteaux-Dinelle J, Richard J, Nguyen DN, Medjahed H, Chen HC, Smith AB, Pazgier M, Finzi A. HIV-1 Envelope Glycoprotein Cell Surface Localization Is Associated with Antibody-Induced Internalization. Viruses 2021; 13:1953. [PMID: 34696383 PMCID: PMC8539245 DOI: 10.3390/v13101953] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/15/2021] [Accepted: 09/27/2021] [Indexed: 12/29/2022] Open
Abstract
To minimize immune responses against infected cells, HIV-1 has evolved different mechanisms to limit the surface expression of its envelope glycoproteins (Env). Recent observations suggest that the binding of certain broadly neutralizing antibodies (bNAbs) targeting the 'closed' conformation of Env induces its internalization. On the other hand, non-neutralizing antibodies (nNAbs) that preferentially target Env in its 'open' conformation, remain bound to Env on the cell surface for longer periods of time. In this study, we attempt to better understand the underlying mechanisms behind the differential rates of antibody-mediated Env internalization. We demonstrate that 'forcing' open Env using CD4 mimetics allows for nNAb binding and results in similar rates of Env internalization as those observed upon the bNAb binding. Moreover, we can identify distinct populations of Env that are differentially targeted by Abs that mediate faster rates of internalization, suggesting that the mechanism of antibody-induced Env internalization partially depends on the localization of Env on the cell surface.
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Affiliation(s)
- Sai Priya Anand
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; (S.P.A.); (J.P.); (J.D.-D.); (J.R.); (H.M.)
- Department of Microbiology and Immunology, McGill University, Montreal, QC H3A 2B4, Canada
| | - Jérémie Prévost
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; (S.P.A.); (J.P.); (J.D.-D.); (J.R.); (H.M.)
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Jade Descôteaux-Dinelle
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; (S.P.A.); (J.P.); (J.D.-D.); (J.R.); (H.M.)
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Jonathan Richard
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; (S.P.A.); (J.P.); (J.D.-D.); (J.R.); (H.M.)
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Dung N. Nguyen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA; (D.N.N.); (M.P.)
| | - Halima Medjahed
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; (S.P.A.); (J.P.); (J.D.-D.); (J.R.); (H.M.)
| | - Hung-Ching Chen
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA; (H.-C.C.); (A.B.S.III)
| | - Amos B. Smith
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104, USA; (H.-C.C.); (A.B.S.III)
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814-4712, USA; (D.N.N.); (M.P.)
| | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; (S.P.A.); (J.P.); (J.D.-D.); (J.R.); (H.M.)
- Department of Microbiology and Immunology, McGill University, Montreal, QC H3A 2B4, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
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9
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Tolbert WD, Nguyen DN, Tehrani ZR, Sajadi MM, Pazgier M. Near-Pan-neutralizing, Plasma Deconvoluted Antibody N49P6 Mimics Host Receptor CD4 in Its Quaternary Interactions with the HIV-1 Envelope Trimer. mBio 2021; 12:e0127421. [PMID: 34281393 PMCID: PMC8406290 DOI: 10.1128/mbio.01274-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/15/2021] [Indexed: 11/20/2022] Open
Abstract
The first step in HIV-1 entry is the attachment of the envelope (Env) trimer to target cell CD4. As such, the CD4-binding site (CD4bs) remains one of the few universally accessible sites for antibodies (Abs). We recently described a method of isolating Abs directly from the circulating plasma and described a panel of broadly neutralizing Abs (bnAbs) from an HIV-1 "elite neutralizer" referred to as patient N49 (N49 Ab lineage [M. M. Sajadi, A. Dashti, Z. R. Tehrani, W. D. Tolbert, et al., Cell 173:1783-1795.e14, 2018, https://doi.org/10.1016/j.cell.2018.03.061]). Here, we describe the molecular details of antigen recognition by N49P6, an Ab of the N49 lineage that recapitulates most of the neutralization breadth and potency of the donor's plasma IgG. Our studies done in the context of monomeric and trimeric antigens indicate that N49P6 combines many characteristics of known CD4bs-specific bnAbs with features that are unique to the N49 Ab lineage to achieve its remarkable neutralization breadth. These include the omission of the CD4 Phe43 cavity and dependence instead on interactions with highly conserved gp120 inner domain layer 3. Interestingly, when bound to BG505 SOSIP, N49P6 closely mimics the initial contact of host receptor CD4 to the adjacent promoter of the HIV-1 Env trimer to lock the trimer in the closed conformation. Altogether, N49P6 defines a new class of near-pan-neutralizing, plasma deconvoluted CD4bs Abs that we refer to as the N49P series. The details of the mechanisms of action of this new Ab class pave the way for the next generation of HIV-1 bnAbs that can be used as vaccine components of therapeutics. IMPORTANCE Binding to target cell CD4 is the first crucial step required for HIV-1 infection. Thus, the CD4-binding site (CD4bs) is one of the most accessible sites for antibodies (Abs). However, due to steric constraints, only a few Abs are capable of targeting this site. Here, we show that the exceptional neutralization breadth and potency of N49P6, a near-pan-neutralizing Ab targeting the CD4bs isolated from the plasma of an HIV-1 "elite neutralizer," patient N49, are due to its signature combination of more typical CD4bs Ab-binding characteristics with unique interactions with the highly conserved gp120 inner domain. In addition, we also present a structural analysis of N49P6 in complex with the BG505 SOSIP trimer to show that N49P6 exhibits remarkable breadth in part by mimicking CD4's quaternary interaction with the neighboring gp120 protomer. In its mode of antigen interaction, N49P6 is unique and represents a new class of CD4bs-specific bnAbs.
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Affiliation(s)
- William D. Tolbert
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Dung N. Nguyen
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Zahra Rikhtegaran Tehrani
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Division of Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Mohammad M. Sajadi
- Division of Vaccine Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Division of Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Medicine, Baltimore VA Medical Center, Baltimore, Maryland, USA
| | - Marzena Pazgier
- Infectious Disease Division, Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
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10
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Bohata J, Nguyen DN, Spáčil J, Komanec M, Ortega B, Vallejo L, Ghassemlooy Z, Zvánovec S. Experimental comparison of DSB and CS-DSB mmW formats over a hybrid fiber and FSO fronthaul network for 5G. Opt Express 2021; 29:27768-27782. [PMID: 34615186 DOI: 10.1364/oe.434334] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 07/29/2021] [Indexed: 06/13/2023]
Abstract
The telecommunication world is experiencing the 5th generation (5G) networks deployment including the use of millimeter wave (mmW) frequency bands to satisfy capacity demands. This leads to the extensive use of optical communications, especially the optical fiber connectivity at the last mile access and the edge networks. In this paper we outline fiber and free space optics (FSO) technologies for use as part of the 5G optical fronthaul network. We investigate two different mmW transmission schemes based on (i) the conventional analog radio over fiber transmission using one Mach-Zehnder modulator (MZM) with double sideband (DSB) optical modulation, and (ii) an optical-based frequency doubling with one MZM biased at the null point to introduce carrier suppression DSB (CS DSB) transmission and second MZM used for data modulation. Both systems are assessed in terms of the error vector magnitude, signal-to-noise ratio, dynamic range and phase noise. We consider a configuration for the fronthaul network in the frequency range 2 (FR2) at 27 and 39 GHz with the scale of bandwidth up to 400 MHz with M-quadrature amplitude modulation and quadrature phase shift keying. Results are also shown for FR1 at 3.5 GHz. Moreover, we investigate for the first time the 5G new radio signal transmission under strong turbulence conditions and show the turbulence-induced FSO link impairment. We finally demonstrate the CS DSB scheme performs well under chromatic dispersion-induced fading for the frequency up to 40 GHz and single mode fiber length of 30 km, whereas the DSB format seems more appropriate for an antenna seamless transmission.
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Nguyen DN, Miao X, Magee M, Tai G, Gorycki PD, Moore KP. 1315. No Dose Adjustment of Metformin with Fostemsavir Coadministration Based on Mechanistic Static and Physiologically Based Pharmacokinetic Models. Open Forum Infect Dis 2020. [PMCID: PMC7776151 DOI: 10.1093/ofid/ofaa439.1497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Fostemsavir (FTR) is an oral prodrug of the first-in-class attachment inhibitor temsavir (TMR) which is being evaluated in patients with multidrug resistant HIV-1 infection. In vitro studies indicated that TMR and its 2 major metabolites are inhibitors of organic cation transporters (OCT)1, OCT2, and multidrug and toxin extrusion transporters (MATEs). To assess the clinical relevance, of OCT and MATE inhibition, mechanistic static DDI prediction with calculated Imax,u/IC50 ratios was below the cut-off limits for a DDI flag based on FDA guidelines and above the cut-off limits for MATEs based on EMA guidelines.
Methods
Metformin is a commonly used probe substrate for OCT1, OCT2 and MATEs. To predict the potential for a drug interaction between TMR and metformin, a physiologically based pharmacokinetic (PBPK) model for TMR was developed based on its physicochemical properties, in vitro and in vivo data. The model was verified and validated through comparison with clinical data. The TMR PBPK model accurately described AUC and Cmax within 30% of the observed data for single and repeat dose studies with or without food. The SimCYP models for metformin and ritonavir were qualified using literature data before applications of DDI prediction for TMR
Results
TMR was simulated at steady state concentrations after repeated oral doses of FTR 600 mg twice daily which allowed assessment of the potential OCT1, OCT2, and MATEs inhibition by TMR and metabolites. No significant increase in metformin systemic exposure (AUC or Cmax) was predicted with FTR co-administration. In addition, a sensitivity analysis was conducted for either hepatic OCT1 Ki, or renal OCT2 and MATEs Ki values. The model output indicated that, a 10-fold more potent Ki value for TMR would be required to have a ~15% increase in metformin exposure
Conclusion
Based on mechanistic static models and PBPK modeling and simulation, the OCT1/2 and MATEs inhibition potential of TMR and its metabolites on metformin pharmacokinetics is not clinically significant. No dose adjustment of metformin is necessary when co-administered with FTR
Disclosures
Xiusheng Miao, PhD, GlaxoSmithKline (Employee) Mindy Magee, Doctor of Pharmacy, GlaxoSmithKline (Employee, Shareholder) Peter D. Gorycki, BEChe, MSc, PhD, GSK (Employee, Shareholder) Katy P. Moore, PharmD, RPh, ViiV Healthcare (Employee)
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12
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Nguyen DN, Redman RL, Horiya S, Bailey JK, Xu B, Stanfield RL, Temme JS, LaBranche CC, Wang S, Rodal AA, Montefiori DC, Wilson IA, Krauss IJ. The Impact of Sustained Immunization Regimens on the Antibody Response to Oligomannose Glycans. ACS Chem Biol 2020; 15:789-798. [PMID: 32109354 PMCID: PMC7091532 DOI: 10.1021/acschembio.0c00053] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
![]()
The high mannose
patch (HMP) of the HIV envelope protein (Env)
is the structure most frequently targeted by broadly neutralizing
antibodies; therefore, many researchers have attempted to use mimics
of this region as a vaccine immunogen. In our previous efforts, vaccinating
rabbits with evolved HMP mimic glycopeptides containing Man9 resulted in an overall antibody response targeting the glycan core
and linker rather than the full glycan or Manα1→2Man
tips of Man9 glycans. A possible reason could be processing
of our immunogen by host serum mannosidases. We sought to test whether
more prolonged dosing could increase the antibody response to intact
glycans, possibly by increasing the availability of intact Man9 to germinal centers. Here, we describe a study investigating
the impact of immunization regimen on antibody response by testing
immunogen delivery through bolus, an exponential series of mini doses,
or a continuously infusing mini-osmotic pump. Our results indicate
that, with our glycopeptide immunogens, standard bolus immunization
elicited the strongest HIV Env-binding antibody response, even though
higher overall titers to the glycopeptide were elicited by the exponential
and pump regimens. Antibody selectivity for intact glycan was, if
anything, slightly better in the bolus-immunized animals.
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Affiliation(s)
- Dung N. Nguyen
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Richard L. Redman
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Satoru Horiya
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Jennifer K. Bailey
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Bokai Xu
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Robyn L. Stanfield
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - J. Sebastian Temme
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Celia C. LaBranche
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Shiyu Wang
- Department of Biology, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Avital A. Rodal
- Department of Biology, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - David C. Montefiori
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Ian A. Wilson
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Isaac J. Krauss
- Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
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13
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Que AT, Nguyen DN, Do NA, Le TA. Dirofilariasis in Vietnam: A case report and brief review. Trop Biomed 2019; 36:475-481. [PMID: 33597409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This report describes a rare case of ophthalmic dirofilariasis in a 68-year-old woman with red and foreign body sensation in the pterygium on her right eye. Slit lamp examination demonstrated a long-slender worm moving in her pterygium. The worm was removed surgically and then identified as Diroflaria repens by sequence analysis of the small subunit ribosomal RNA (SSU) gene. The situation of dirofilariasis in Vietnam has been reviewed. Since the first described case in 2010 there have been thirteen cases reported that suggested the emerging trend of the disease. Most of the documented cases of human dirofilariasis recorded in Vietnam presented with ocular infections and the responsible agent was D. repens. With the increase of reported cases of human, much more attention should be paid on control as well as diagnosis and treatment of dirofilariasis in Vietnam.
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Affiliation(s)
- A T Que
- Department of Tropical disease, Vinh Hospital of Frienship General, Lenin boulevard, Vinh, Nghe An, Vietnam
| | - D N Nguyen
- Department of Ophthalmology, 103 hospital, Vietnam Military Medical University, Phung Hung, Ha Dong, Ha Noi, Vietnam
| | - N A Do
- Department of Parasitology, Vietnam Military Medical University, Phung Hung, Ha Dong, Ha Noi, Vietnam
| | - T A Le
- Department of Parasitology, Vietnam Military Medical University, Phung Hung, Ha Dong, Ha Noi, Vietnam
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Nguyen DN, Xu B, Stanfield RL, Bailey JK, Horiya S, Temme JS, Leon DR, LaBranche CC, Montefiori DC, Costello CE, Wilson IA, Krauss IJ. Oligomannose Glycopeptide Conjugates Elicit Antibodies Targeting the Glycan Core Rather than Its Extremities. ACS Cent Sci 2019; 5:237-249. [PMID: 30834312 PMCID: PMC6396197 DOI: 10.1021/acscentsci.8b00588] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Indexed: 06/01/2023]
Abstract
Up to ∼20% of HIV-infected individuals eventually develop broadly neutralizing antibodies (bnAbs), and many of these antibodies (∼40%) target a region of dense high-mannose glycosylation on gp120 of the HIV envelope protein, known as the "high-mannose patch" (HMP). Thus, there have been numerous attempts to develop glycoconjugate vaccine immunogens that structurally mimic the HMP and might elicit bnAbs targeting this conserved neutralization epitope. Herein, we report on the immunogenicity of glycopeptides, designed by in vitro selection, that bind tightly to anti-HMP antibody 2G12. By analyzing the fine carbohydrate specificity of rabbit antibodies elicited by these immunogens, we found that they differ from some natural human bnAbs, such as 2G12 and PGT128, in that they bind primarily to the core structures within the glycan, rather than to the Manα1 → 2Man termini (2G12) or to the whole glycan (PGT128). Antibody specificity for the glycan core may result from extensive serum mannosidase trimming of the immunogen in the vaccinated animals. This finding has broad implications for vaccine design aiming to target glycan-dependent HIV neutralizing antibodies.
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Affiliation(s)
- Dung N. Nguyen
- Department
of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Bokai Xu
- Department
of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Robyn L. Stanfield
- Department
of Integrative Structural and Computational Biology and the Skaggs
Institute for Chemical Biology, The Scripps
Research Institute, La Jolla, California 92037, United States
| | - Jennifer K. Bailey
- Department
of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Satoru Horiya
- Department
of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - J. Sebastian Temme
- Department
of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Deborah R. Leon
- Department
of Biochemistry, Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, Massachusetts 02215, United States
| | - Celia C. LaBranche
- Department
of Surgery, Duke University Medical Center, Durham, North Carolina 27710, United States
| | - David C. Montefiori
- Department
of Surgery, Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Catherine E. Costello
- Department
of Biochemistry, Center for Biomedical Mass Spectrometry, Boston University School of Medicine, Boston, Massachusetts 02215, United States
| | - Ian A. Wilson
- Department
of Integrative Structural and Computational Biology and the Skaggs
Institute for Chemical Biology, The Scripps
Research Institute, La Jolla, California 92037, United States
| | - Isaac J. Krauss
- Department
of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, United States
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Stanfield RL, Nguyen DN, Krauss IJ, Wilson IA. Synthetic glycopeptide selected by directed evolution in complex with anti-HIV-1 Fab 2G12. Acta Crystallogr A Found Adv 2018. [DOI: 10.1107/s0108767318098215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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16
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Abstract
Recently, we reported a directed evolution method which enabled us to discover sequences of glycopeptides that bind with picomolar affinity to HIV antibody 2G12 and are of interest as HIV vaccine candidates. In this manuscript, we describe the syntheses of several of these large (~11-12 kDa) glycopeptides by a combination of fast flow peptide synthesis and click chemistry. We also discuss the optimization of their attachment to carrier protein CRM197, affording antigenic and immunogenic conjugates ready for animal vaccination.
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Affiliation(s)
| | | | - Satoru Horiya
- Department of Chemistry, Brandeis University, 415 South St. MS 015, Waltham, MA 02454-9110, USA
| | - Isaac J. Krauss
- Department of Chemistry, Brandeis University, 415 South St. MS 015, Waltham, MA 02454-9110, USA
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17
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Rovang DC, Lamppa DC, Cuneo ME, Owen AC, McKenney J, Johnson DW, Radovich S, Kaye RJ, McBride RD, Alexander CS, Awe TJ, Slutz SA, Sefkow AB, Haill TA, Jones PA, Argo JW, Dalton DG, Robertson GK, Waisman EM, Sinars DB, Meissner J, Milhous M, Nguyen DN, Mielke CH. Pulsed-coil magnet systems for applying uniform 10-30 T fields to centimeter-scale targets on Sandia's Z facility. Rev Sci Instrum 2014; 85:124701. [PMID: 25554308 DOI: 10.1063/1.4902566] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Sandia has successfully integrated the capability to apply uniform, high magnetic fields (10-30 T) to high energy density experiments on the Z facility. This system uses an 8-mF, 15-kV capacitor bank to drive large-bore (5 cm diameter), high-inductance (1-3 mH) multi-turn, multi-layer electromagnets that slowly magnetize the conductive targets used on Z over several milliseconds (time to peak field of 2-7 ms). This system was commissioned in February 2013 and has been used successfully to magnetize more than 30 experiments up to 10 T that have produced exciting and surprising physics results. These experiments used split-magnet topologies to maintain diagnostic lines of sight to the target. We describe the design, integration, and operation of the pulsed coil system into the challenging and harsh environment of the Z Machine. We also describe our plans and designs for achieving fields up to 20 T with a reduced-gap split-magnet configuration, and up to 30 T with a solid magnet configuration in pursuit of the Magnetized Liner Inertial Fusion concept.
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Affiliation(s)
- D C Rovang
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - D C Lamppa
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - M E Cuneo
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - A C Owen
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - J McKenney
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - D W Johnson
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - S Radovich
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - R J Kaye
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - R D McBride
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - C S Alexander
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - T J Awe
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - S A Slutz
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - A B Sefkow
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - T A Haill
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - P A Jones
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - J W Argo
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - D G Dalton
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - G K Robertson
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - E M Waisman
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - D B Sinars
- Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185, USA
| | - J Meissner
- Milhous Company, 144 South Main Street, Amherst, Virginia 24521, USA
| | - M Milhous
- Milhous Company, 144 South Main Street, Amherst, Virginia 24521, USA
| | - D N Nguyen
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA
| | - C H Mielke
- Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA
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18
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Sarina EA, Olmstead MM, Nguyen DN, Groziak MP. 1-Hydroxy-1H-benzo[d][1,2,6]oxazaborinin-4(3H)-one. Acta Crystallogr C 2013; 69:183-5. [PMID: 23377688 DOI: 10.1107/s0108270113000681] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 01/08/2013] [Indexed: 11/11/2022] Open
Abstract
The structure of the title compound, C(7)H(6)BNO(3), a new boron heterocycle, prepared by the condensation of (2-ethoxycarbonylphenyl)boronic acid and hydroxylamine, reveals the specific mode of intramolecular condensation between a phenylboronic acid and an ortho hydroxamic acid substituent. The crystal structure shows that dehydration occurs to form a planar oxazaborinine ring possessing both phenol-like B-O-H and lactam functional groups. In the extended structure, intermolecular hydrogen bonding generates a 14-membered ring. To our knowledge, this is the first crystal structure determination involving a six-membered ring that exhibits consecutive B-OH, O, NH, and C=O functional groups.
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Affiliation(s)
- Evan A Sarina
- Department of Chemistry, University of California, One Shields Avenue, Davis, CA 95616-5292, USA
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20
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Abstract
BACKGROUND In Chile, a country with a so called emerging market-economy, where rapid social and life style changes are taking place, women and the more socially disadvantaged are more at risk of becoming depressed. METHODS Results of several studies are summarized in the context of a review of the literature. RESULTS A third of Chilean women have depressive and/or anxiety symptoms during midpregnancy, while prevalence figures both in the early and the late postpartum period increase up to 50% in most studies. If strict operational criteria describing well defined depressive disorders are used postnatally, differences in prevalence and incidence figures arise depending on socioeconomic status. Whereas incidence rates for postpartum depression (around 9%) are very similar to those found in the northern hemisphere and do not appear to vary across different socioeconomic levels, higher prevalence rates are found among women from lower socioeconomic status. LIMITATIONS The studies focused on current diagnostic entities and did not consider different clusters or dimensions. CONCLUSION A shared biological etiology may be triggered by the physiology of childbirth and account for similarities in incidence across different socioeconomic levels. In turn, we hypothesize that the higher prevalence of postpartum depression (PPD) in Chilean women from lower socioeconomic status is the result of pre-existing depression and is not caused by more new cases of the illness.
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Affiliation(s)
- E Jadresic
- Faculty of Medicine, University of Chile, Avenida La Paz 1003, Santiago, Chile.
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21
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Nguyen DN, Rohrbaugh M, Lai Z. The Drosophila homolog of Onecut homeodomain proteins is a neural-specific transcriptional activator with a potential role in regulating neural differentiation. Mech Dev 2000; 97:57-72. [PMID: 11025207 DOI: 10.1016/s0925-4773(00)00431-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
We report here the characterization of the Drosophila homolog of the onecut homeobox gene, which encodes a protein product with one cut domain and one homeodomain. We present evidence that D-Onecut can bind to similar DNA sequences with high specificity and affinity as other Onecut proteins through the highly conserved cut domain and homeodomain. Interestingly, the cut domain alone can mediate DNA-binding, but the homeodomain cannot. However, depending upon the promoter context, we observed cooperative interactions between the two domains to confer high DNA-binding affinity and specificity. D-Onecut appears to be a moderate transcriptional activator and functions as a nuclear protein in neuronal tissues of both the CNS and PNS during development and in the adult. In the eye, D-Onecut expression is independent of glass, a transcriptional regulator of R cell differentiation. Taken together, our results suggest a role for D-Onecut in the regulation of some aspects of neural differentiation or maintenance. In support of this notion, overexpression of a putative dominant negative form of D-Onecut during eye development does not affect early cell fate specification, but severely affects photoreceptor differentiation.
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Affiliation(s)
- D N Nguyen
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
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22
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ver Elst KM, Spapen HD, Nguyen DN, Garbar C, Huyghens LP, Gorus FK. Cardiac troponins I and T are biological markers of left ventricular dysfunction in septic shock. Clin Chem 2000; 46:650-7. [PMID: 10794747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
BACKGROUND Cardiac depression in severe sepsis and septic shock is characterized by left ventricular (LV) failure. To date, it is unclear whether clinically unrecognized myocardial cell injury accompanies, causes, or results from this decreased cardiac performance. We therefore studied the relationship between cardiac troponin I (cTnI) and T (cTnT) and LV dysfunction in early septic shock. METHODS Forty-six patients were consecutively enrolled, fluid-resuscitated, and treated with catecholamines. Cardiac markers were measured at study entry and after 24 and 48 h. LV function was assessed by two-dimensional transesophageal echocardiography. RESULTS Increased plasma concentrations of cTnI (>/=0.4 microgram/L) and cTnT (>/=0.1 microgram/L) were found in 50% and 36%, respectively, of the patients at one or more time points. cTnI and cTnT were significantly correlated (r = 0.847; P <0.0001). Compared with cTnI-negative patients, cTnI-positive subjects were older, presented higher Acute Physiology and Chronic Health Evaluation II scores at diagnosis, and tended to have a worse survival rate and a more frequent history of arterial hypertension or previous myocardial infarction. In contrast, the two groups did not differ in type of infection or pathogen, or in dose and type of catecholamine administered. Continuous electrocardiographic monitoring in all patients and autopsy in 12 nonsurvivors did not disclose the occurrence of acute ischemia during the first 48 h of observation. LV dysfunction was strongly associated with cTnI positivity (78% vs 9% in cTnI-negative patients; P <0.001). In multiple regression analysis, both cTnI and cTnT were exclusively associated with LV dysfunction (P <0.0001). CONCLUSIONS These findings suggest that in septic shock, clinically unrecognized myocardial cell injury is a marker of LV dysfunction. The latter condition tends to occur more often in severely ill older patients with underlying cardiovascular disease. Further studies are needed to determine the extent to which myocardial damage is a cause or a consequence of LV dysfunction.
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Affiliation(s)
- K M ver Elst
- Department of Clinical Chemistry, Academic Hospital Vrije Universiteit Brussel (AZ-VUB), B-1090 Brussels, Belgium
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23
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Smets D, Spapen H, Diltoer M, Nguyen DN, Hubloue I, Huyghens L. Liver perfusion and hepatocellular inflammatory response in sepsis. Acta Clin Belg 1999; 54:201-6. [PMID: 10544510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Sepsis is characterized by disturbances in liver perfusion and alterations in intrahepatic cellular functions and interactions. This provokes structural and functional liver damage as well as hepatocellular activation that is believed to perpetuate the immuno-inflammatory response. Changes in hepatic perfusion during sepsis are still poorly understood due to the heterogeneity of septic animal models and the difficult accessibility of the hepatic circulation in humans. Sinusoidal blood flow is severely compromised during sepsis due to a decline in perfused sinusoidal area in association with a decrease in sinusoidal flow velocity. Imbalances in the production of nitric oxide may account for these (micro) circulatory disorders. Interactions between liver macrophages, activated endothelial cells and hepatocytes determine the intensity of inflammation and contribute to initial liver damage. Hepatocellular injury is then enhanced by attracted and invading neutrophils. The management of hepatic dysfunction during sepsis is largely supportive and based on prevention and vigorous resuscitation including early nutritional support and adequate oxygenation. Interestingly, experimental studies suggest that pharmacological interventions with significant hemodynamic effects, such as dobutamine and nitric oxide synthase inhibitors, may adversely affect the liver during the septic process.
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Affiliation(s)
- D Smets
- Intensive Care Department, Academic Hospital, Vrije Universiteit Brussel, Belgium
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24
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Nguyen DN, Liu Y, Litsky ML, Reinke R. The sidekick gene, a member of the immunoglobulin superfamily, is required for pattern formation in the Drosophila eye. Development 1997; 124:3303-12. [PMID: 9310325 DOI: 10.1242/dev.124.17.3303] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In the Drosophila eye imaginal disc the photoreceptor cells (R cells) differentiate according to a precise spatial and temporal order. The sidekick (sdk) gene is necessary to prevent extra R cells from differentiating during eye disc development. The extra cell appears between R3 and R4 early in R cell clusters and is most likely the result of the mystery cell inappropriately differentiating as an R cell. Mosaic analysis shows that sdk is required neither in the R cells nor in the extra cell, suggesting that sdk is necessary in the surrounding undifferentiated cells. The sdk gene codes for a protein that is a member of the immunoglobulin superfamily, having six immunoglobulin domains, thirteen fibronectin repeats and a transmembrane domain. The protein structure is consistent with its participation in cell-cell interaction during eye development.
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Affiliation(s)
- D N Nguyen
- Albert Einstein College of Medicine, Department of Developmental and Molecular Biology, Bronx, NY 10461, USA
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25
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Felder CC, Nielsen A, Briley EM, Palkovits M, Priller J, Axelrod J, Nguyen DN, Richardson JM, Riggin RM, Koppel GA, Paul SM, Becker GW. Isolation and measurement of the endogenous cannabinoid receptor agonist, anandamide, in brain and peripheral tissues of human and rat. FEBS Lett 1996; 393:231-5. [PMID: 8814296 DOI: 10.1016/0014-5793(96)00891-5] [Citation(s) in RCA: 239] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Anandamide (arachidonylethanolamide) is a novel lipid neurotransmitter first isolated from porcine brain which has been shown to be a functional agonist for the cannabinoid CB1 and CB2 receptors. Anandamide has never been isolated from human brain or peripheral tissues and its role in human physiology has not been examined. Anandamide was measured by LC/MS/MS and was found in human and rat hippocampus (and human parahippocampal cortex), striatum, and cerebellum, brain areas known to express high levels of CB1 cannabinoid receptors. Significant levels of anandamide were also found in the thalamus which expresses low levels of CB1 receptors. Anandamide was also found in human and rat spleen which expresses high levels of the CB2 cannabinoid receptor. Small amounts of anandamide were also detected in human heart and rat skin. Only trace quantities were detected in pooled human serum, plasma, and CSF. The distribution of anandamide in human brain and spleen supports its potential role as an endogenous agonist in central and peripheral tissues. The low levels found in serum, plasma, and CSF suggest that it is metabolized in tissues where it is synthesized, and that its action is probably not hormonal in nature.
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Affiliation(s)
- C C Felder
- Laboratory of Cell Biology, National Institute of Mental Health, Bethesda, MD 20892-4090, USA.
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Zhang H, Nguyen DN, Spapen H, Moock M, Maciel F, Vincent JL. Sodium nitroprusside does not influence tissue oxygen extraction capabilities during a critical reduction in oxygen delivery. Cardiovasc Res 1995; 30:240-5. [PMID: 7585811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
By its regulating effects on blood vessel tone, nitric oxide (NO) may play an important role in the coupling of oxygen delivery (DO2) to metabolic rate. We reasoned that if endogenous NO synthesis is an important modulator of oxygen extraction ratio (O2ER), then administration of a NO donor will alter oxygen extraction capabilities during a fall in blood flow. We studied the effects of the NO donor, nitroprusside, on the relationship between DO2 and oxygen uptake (VO2) during an acute reduction in DO2 induced by cardiac tamponade. Twenty-one healthy, anaesthetised, mechanically ventilated dogs were randomly divided into 3 groups. Group 1 (n = 7) served as control; Groups 2 and 3 were given sodium nitroprusside at 1.0 microgram/kg.min (n = 7), and 2.5 micrograms/kg.min intravenously (n = 7), respectively. All animals were given normal saline i.v. at a rate of 20 ml/kg.h throughout the study. Cardiac tamponade was induced by bolus injections of normal saline into the pericardial space. In the control animals the critical DO2 (DO2crit) was found at 10.1 +/- 1.5 ml/kg.min and critical O2ER (O2ERcrit) at 63.3 +/- 10.9%. Nitroprusside at the lower dose decreased systemic vascular resistance but did not significantly influence arterial pressure, cardiac output, DO2 or VO2; neither DO2crit nor O2ERcrit was altered (9.3 +/- 2.9 ml/kg.min and 70.4 +/- 20.9%). Nitroprusside at the higher dose induced significant decreases in mean arterial pressure and systemic vascular resistance, but had no significant effect on cardiac output. DO2crit (9.2 +/- 2.0 ml/kg.min) and O2ERcrit (59.8 +/- 13.2%) were similar to the control group.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H Zhang
- Department of Intensive Care, Erasme University Hospital, Free University of Brussels, Belgium
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Abstract
The advent of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and electrospray ionization mass spectrometry (ESI-MS) in the last 5 years has greatly enhanced the area of protein mass spectrometry. This paper presents an overview of the applications of protein mass spectrometry in the area of analytical biotechnology, particularly as related to biopharmaceutical research and development. These applications include the determination of protein molecular mass, peptide mapping, peptide sequencing, ligand binding, determination of disulfide bonds, active site characterization of enzymes, protein self-association and protein folding/higher order structural characterization.
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Affiliation(s)
- D N Nguyen
- Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis 46285, USA
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Zhang H, Spapen H, Nguyen DN, Rogiers P, Bakker J, Vincent JL. Effects of N-acetyl-L-cysteine on regional blood flow during endotoxic shock. Eur Surg Res 1995; 27:292-300. [PMID: 7589000 DOI: 10.1159/000129412] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We previously reported that N-acetyl-L-cysteine (NAC), an oxygen free-radical scavenger, can increase the oxygen extraction capabilities during endotoxic shock when blood flow is progressively reduced. In the present study, we investigated whether the protective effects of NAC are related to an improvement in regional blood flow following endotoxemia. Fourteen anesthetized, saline-infused and ventilated dogs were divided into two groups: 7 dogs received NAC (150 mg/kg, followed by a 20 mg/kg.h infusion), and the other 7 dogs served as a control time-matching group. Thirty minutes later all the dogs received Escherichia coli endotoxin (2 mg/kg) i.v. A saline infusion was started 30 min after endotoxin challenge to restore pulmonary artery occlusion pressure to baseline and maintain it constant. Regional blood flow was measured by ultrasonic volume flowmeter. In the control group, arterial pressure, left ventricular stroke work index and systemic vascular resistance remained lower than baseline. Mesenteric, renal and femoral arterial blood flow increased but only femoral blood flow returned to baseline levels. In the NAC group, cardiac index and left ventricular stroke work index remained higher and systemic and pulmonary vascular resistance were lower than in the control group. Blood flow in mesenteric, renal and especially femoral arteries was higher than in the control group. Fractional blood flow increased only in the femoral artery. PaO2 and PvO2 had similar courses in the two groups. A higher venous admixture was associated with a higher cardiac index and a lower pulmonary vascular resistance in the NAC group. Oxygen delivery and oxygen-uptake were higher in the NAC-treated than in the control animals throughout the study.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H Zhang
- Department of Intesive Care, Erasme University Hospital, Free University of Brussels, Belgium
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Abstract
By its microvascular and anti-inflammatory actions, prostaglandin E1 (PGE1) has been suggested both in animal models and in humans to have a therapeutic value in sepsis. To investigate whether PGE1 could improve the oxygen extraction capabilities in severe sepsis, our study focused on the relationship between oxygen uptake (VO2) and oxygen delivery (DO2) during an acute reduction in blood flow induced by cardiac tamponade in endotoxic dogs. Thirty anesthetized, ventilated dogs were divided into three groups. A first group (N = 10) served as a control receiving 20 ml/kg/hr of saline intravenously. A second group (N = 10) received PGE1 at 100 ng/kg/min along with the same saline infusion. A third group (N = 10) received the same dose of PGE1 with only 1 ml/kg/hr of saline. Thirty minutes after the initiation of this therapy, Escherichia coli endotoxin (2 mg/kg) was injected in each dog. In each group, the administration of PGE1, fluids, or both was continued throughout the study. Tamponade was then induced by repeated bolus injections of warm saline into the pericardial space. Steady-state measurements of VO2 (derived from the expired gases) and DO2 (the product of cardiac index and oxygen content) were obtained sequentially after each saline injection. The administration of PGE1 + fluids resulted in significant increases in stroke volume, cardiac index, and DO2 and reductions in systemic and pulmonary vascular resistance. Stroke volume and cardiac index were lower in the PGE1 alone than in the PGE1 + fluids group. The VO2 levels at critical DO2 (DO2crit) were identical. However, DO2crit, which was 12.2 +/- 2.8 ml/kg/min in the control group, was significantly decreased to 9.8 +/- 2.0 ml/kg/min in the PGE1 + fluids and to 9.3 +/- 2.7 ml/kg/min in the PGE1 alone group (both P < 0.05). Critical oxygen extraction ratio (O2ERcrit) which was 47 +/- 14% in the control group, was increased to 63 +/- 16% in the PGE1 + fluids group and to 61 +/- 17% in the PGE1 alone group (both P < 0.05). To investigate whether PGE1 also improves oxygen extraction capabilities in the absence of endotoxin, a second series of experiments was performed in 14 dogs, receiving saline alone (Control, N = 7) or plus PGE1 at 100 ng/kg/min (PGE1, N = 7). DO2crit was 10.7 +/- 2.9 ml/kg/min in the PGE1 group vs 10.1 +/- 1.8 ml/kg/min in the control group (NS). O2ERcrit tended to be higher in the PGE1 group than that in the control group (68 +/- 13% vs 60 +/- 15%, P = 0.054).(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- H Zhang
- Department of Intensive Care, Erasme University Hospital, Free University of Brussels, Belgium
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30
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Abstract
Pentoxifylline (PTX), a xanthine derivative used in the treatment of circulatory insufficiency, has been found to have protective effects in different models of sepsis. We hypothesized that this drug might improve the cellular oxygen availability following endotoxin challenge by increasing oxygen delivery (DO2) and/or tissue oxygen extraction. The oxygen extraction capabilities were studied during a reduction in blood flow induced by cardiac tamponade. Fourteen anesthetized, ventilated, and paralyzed dogs, received intravenous 2 mg/kg of Escherichia coli endotoxin followed by a continuous infusion of 20 ml/kg.h of saline. 30 min later tamponade was induced by repeated bolus injections of warm saline into the pericardial space. Seven dogs were pretreated with PTX as an intravenous bolus of 20 mg/kg, followed by a continuous infusion at 20 mg/kg.h, and the other seven dogs served as a control group. PTX largely attenuated the systemic and pulmonary vasoconstriction observed in the control group and resulted in significant increases in cardiac index, DO2 and oxygen consumption (VO2). PTX also improved ventilation/perfusion matching in the lungs as indicated by a higher PaO2 and PvO2 and a lower venous admixture than in the untreated group during cardiac tamponade (both p < .05). In addition, the critical DO2 (DO2 crit) was lower and the critical oxygen extraction ratio was higher in the PTX treated than in the control group (9.1 +/- 1.8 vs. 11.6 +/- 2.4 ml/kg.min, and 70.6 +/- 14.0 vs. 49.3 +/- 14.6%, both p < .05). The VO2/DO2 dependency slope was also steeper in the PTX-treated than in the control group (.80 +/- .28 vs. .43 +/- .19, p < .05).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H Zhang
- Department of Intensive Care, Erasme University Hospital, Free University of Brussels, Belgium
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31
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Abstract
Because oxygen free radicals have been implicated in the endothelial cell damage and in the myocardial depression occurring during severe sepsis, we investigated whether N-acetyl-L-cysteine (NAC) could influence the oxygen extraction capabilities during an acute reduction in blood flow induced by cardiac tamponade after endotoxin challenge. Sixteen anesthetized, saline-infused, and ventilated dogs received Escherichia coli endotoxin (2 mg/kg) 30 min before tamponade was induced by repeated bolus injections of warm saline into the pericardial space. Thirty minutes before endotoxin administration, nine dogs received NAC (150 mg/kg, followed by a 20 mg.kg-1.h-1 infusion); the other seven dogs served as a control group. The NAC group maintained higher cardiac index, oxygen delivery (DO2), and left ventricular stroke work index, but lower systemic and pulmonary vascular resistance, than the control group. The oxygen uptake (VO2) levels at critical DO2 (DO2crit) were identical in the two groups. However, DO2crit was significantly lower in the NAC than in the control group (8.1 +/- 1.7 vs. 10.8 +/- 1.8 ml.kg-1.min-1, P < 0.01). Critical oxygen extraction ratio and the slope of the VO2-to-DO2-dependent line were higher in the NAC than in the control group (72 +/- 14 vs. 53 +/- 15% and 0.80 vs. 0.56, respectively; both P < 0.05). The peak lactate and the maximal tumor necrosis factor (TNF) levels were lower in the NAC than in the control group (5.2 +/- 0.4 vs. 7.6 +/- 0.4 mM, and 0.14 +/- 0.03 vs. 1.21 +/- 0.58 ng/ml, respectively; both P < 0.01). NAC significantly increased glutathione peroxidase activity.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H Zhang
- Department of Intensive Care, Erasme University Hospital, Free University of Brussels, Belgium
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32
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Abstract
The reverse hemolytic plaque assay (RHPA) was used in this study to further characterize the mechanism whereby low concentrations of dopamine (DA) stimulate PRL secretion in vitro. Female Sprague-Dawley rats were used as a source of anterior pituitary cells for the RHPA. Pituitary cells were infused into Cunningham chambers along with a suspension of protein-A-coated ovine red blood cells. Excess cells were rinsed from the chambers leaving a monolayer of cells attached to the glass. The cells were then incubated with solutions containing PRL antiserum (1:40) and various concentrations of DA. After 4 h, a solution containing guinea pig complement (1:60) was infused into the chambers. Thirty minutes later, the cells were fixed and plaques (zones of hemolysis) surrounding PRL-producing cells (lactotrophs) were measured and used as an index of the amount of PRL secreted. Control cells that received no DA had a mean plaque area of 8,000 microns 2 and two distinct subpopulations of plaque sizes. This biphasic population of cells consisted of a small and a large plaque producing population. The mean plaque area surrounding lactotrophs was significantly (P less than 0.05) decreased if 1 microM or 10 microM DA was present (4,500 microns 2 and 3,500 microns 2, respectively). These cells which received inhibitory concentrations of DA demonstrated a monophasic distribution of plaque-forming cells. On the other hand, mean plaque area was significantly (P less than 0.05) increased if 0.1 nM or 1 nM DA was presented to the cells (15,000 microns 2 and 14,500 microns 2, respectively). These cells receiving stimulatory doses of DA exhibited a multiphasic distribution of plaque-forming cells. The possibility that the two physiological opposing actions of DA on PRL secretion might be mediated by different GTP binding proteins was also examined using cholera toxin (CTX) and pertussis toxin (PTX). Anterior pituitary cells were pretreated with either CTX (50 micrograms/ml) or PTX (5 micrograms/ml) for 1 h before initiation of the RHPA. In the RHPA, cells received no DA, a stimulatory dose of DA (0.1 nM), or a inhibitory dose of DA (10 microM). The effects of toxin pretreatment on mean plaque area of DA-treated cells was determined. PTX pretreatment significantly attenuated the inhibitory effects of DA while having no effect on the stimulatory effects of DA on PRL secretion. CTX significantly (P less than 0.05) potentiated the stimulatory effects of DA on PRL secretion and had no effect on inhibition.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- T P Burris
- Department of Biological Science, Florida State University, Tallahassee 32306-3050
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33
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Abstract
The contribution of the uterus to the regulation of PRL secretion in lactating dams and cycling female rats was investigated. Lactating animals were hysterectomized or sham operated 2 days after parturition, and the number of pups was adjusted to eight. Blood samples for PRL RIA were obtained through intra-atrial cannulae implanted 2 days before experimentation. In order to study the PRL secretory profile in undisturbed freely lactating rats, blood samples were taken every 2 h for 24 h starting at 1400 h. During early lactation (days 7-8), hysterectomy did not alter the PRL secretory profile compared to that of sham-operated controls. On days 14-15 post partum, PRL secretion followed a characteristic bimodal pattern showing two PRL surges at 1800 h and 0600 h. After hysterectomy, the early morning PRL surge disappeared and PRL secretion showed an unimodal daily rhythm reaching its peak at 1800 h. The possible effect of the absence of the uterus on suckling-induced PRL release at various stages of lactation was studied. On days 7-8, suckling stimuli after 4 h of pup deprivation induced robust PRL release. Hysterectomy did not significantly alter PRL release at this earlier stage of lactation. In control groups, the suckling-induced PRL secretory response markedly declined as the postpartum period advanced. On the other hand, the hysterectomized animals retained significantly greater responsiveness to suckling during the second half of lactation. These data indicate an inhibitory influence of the uterus on PRL secretion. The onset of this uterine effect is considerably delayed, and its influence became prominent only at a later phase of lactation. The effect of length of pup deprivation preceding the suckling stimulus, in combination with hysterectomy, was also investigated. Hysterectomy significantly increased suckling-induced PRL release after 4 and 24 h separation compared to the sham-hysterectomized animals. When the separation was longer than 48 h, the inducibility of PRL release by suckling declined and was not influenced by hysterectomy. In order to study the possible influence of the uterus on PRL secretion during the estrous cycle, regularly cycling female rats were hysterectomized at diestrus 1. Twelve days later the animals were cannulated, and serial blood samples were taken during the subsequent proestrus. Hysterectomy did not alter the PRL surge which occurred on the afternoon of proestrus indicating that the uterus does not have a major function in regulating PRL secretion on proestrus. In conclusion, hysterectomy significantly delayed the extinction of suckling-induced PRL release revealing the active role of the uterus in the regulation of this neuroendocrine reflex.
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Affiliation(s)
- B Kanyicska
- Department of Biological Science, Florida State University, Tallahasse 32306
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